Apparatus for effecting electrical connections with multiple contact points

Abstract

An improved construction is provided for interfacing board type interconnect system apparatus for use in effecting a multiplicity of concurrent, respective, electrical connections with closely spaced, typically irregularly arranged, contactable, electrically conductive zones of a printed circuit board or the like, such as is required, for example, in the testing of such devices. The apparatus employs a preferably laminated assembly of stacked, electrically insulative plates, including support plates pre-drilled to provide a matrix of relatively small and closely spaced holes for mounting spring pin type contactor assemblies and backing plates for physical reinforcement of the support plates and pre-drilled to provide a matrix of relatively larger and less closely spaced openings each communicating with a plurality of the mentioned holes to present a clearance path for electrical leads associated with the contactor assemblies. The construction utilized minimizes the drilling required to produce interfacing boards of requisite physical strength, precision, reliability and versatility for use in effecting a multiplicity of electrical connections with the test points of printed circuit board or similar devices having various arrangements of contactable zones thereon.

I claim: 
     
       1. In apparatus for effecting concurrent, respective, forceful engagements to make electrical connections with each of a multiplicity of generally coplanar, electrically conductive zones arranged in a permisssably irregular pattern upon an electrical device such as, for example, a printed circuit board to be tested: an electrically insulative holding assembly having a pair of oppositely facing, substantially flat surfaces thereon and provided with a multiplicity of holes extend therethrough and oppositely communicating with said surfaces,   said holes having respective central axes and including a particular hole corresponding with each of said zones respectively,   said holding assembly being adapted for disposition relative to said device in an operative position juxtaposing one of said surfaces in facing relationship with said zones with said axes of said particular holes in respective alignment with corresponding ones of said zones;   a multiplicity of electrically conductive contactor assemblies, including a contactor assembly for at least each of said particular holes respectively, each having a base portion mounted in a corresponding hole and a contacting portion extending from said base portion and away from said one surface in a direction substantially aligned with said axis of the corresponding hole for forceful engagement of said contacting portions with said device, including forceful engagement of said contacting portion of each of said contactor assemblies mounted in one of said particular holes with a corresponding one of said zones, when said holding assembly is in said operative position;   a reinforcing assembly having a substantially flat face thereon and provided with a plurality of openings extending therethrough and communicating with said face,   said openings having respective central axes,   at least certain of said openings having a larger, transverse, cross-sectional size than said holes;   means for securing said holding and reinforcing assemblies in a predetermined interengaged relationship to each other with said face of said reinforcing assembly in backing engagement with the other of said surfaces of said holding assembly,   the arrangement of said axes of said holes, the arrangement of said axes of said openings and the relative, lateral, cross-sectional sizes of said holes and said openings being such that, when said holding and reinforcing assemblies are in said predetermined relationship thereof, the extremity of each of said openings adjacent said face is in communication with the extremity of a plurality of said holes adjacent said other surface; and   electrically conductive, connecting means for each contactor assembly respectively, electrically coupled with said base portion of the latter and extending therefrom through the opening communicating with the hole in which the corresponding contactor assembly is mounted to a location at which said connecting means is adapted for being coupled with external electrical circuitry.   
     
     
       2. In apparatus as set forth in claim 1, wherein: said surfaces are substantially parallel, and   said axes of said holes are substantially perpendicular to said surfaces.   
     
     
       3. In apparatus as set forth in claim 2, wherein: said axes of said openings are substantially perpendicular to said face.   
     
     
       4. In apparatus as set forth in claim 2, wherein: said axes of said holes are regularly disposed at locations defining intersection points of a grid-like pattern.   
     
     
       5. In apparatus as set forth in claim 4, wherein: said axes of said openings are regularly disposed at locations defining intersection points of a grid-like pattern having its intersection points more widely spaced than those of said grid-like pattern of said axes of said holes.   
     
     
       6. In apparatus as set forth in claim 2, wherein: said holding assembly includes a plurality of electrically insulative, support plates in stacked relationship.   
     
     
       7. In apparatus as set forth in claim 6, wherein: said support plates include a primary locator plate presenting said one surface of said holding assembly and of lesser thickness than other of said support plates.   
     
     
       8. In apparatus as set forth in claim 6, wherein: said holes in said holding assembly are presented by aligned perforations drilled through each of said support plates.   
     
     
       9. In apparatus as set forth in claim 8, wherein: said axes of said holes are arranged in a rectangular, matrix pattern.   
     
     
       10. In apparatus as set forth in claim 9, wherein: the spacing between said axes of adjacent ones of said holes is no greater than about 0.1 inch.   
     
     
       11. In apparatus as set forth in claim 10, wherein: the spacing between said axes of adjacent ones of said holes is approximately 0.05 inch.   
     
     
       12. In apparatus as set forth in claim 11, wherein: said holes are substantially cylindrical and have a diameter of approximately 0.038 inch.   
     
     
       13. In apparatus as set forth in either of claims 1 or 6, wherein: said contacting portion of each of said contactor assemblies is yieldably biased in said direction away from said base portion thereof.   
     
     
       14. In apparatus as set forth in claim 13, wherein: the force of yieldable biasing of each of said contacting portions away from the base portion associated therewith being in the range of about 2 to about 8 ounces.   
     
     
       15. In apparatus as set forth in either of claims 1 or 6, wherein: said reinforcing assembly includes a plurality of electrically insulative, backing plates in stacked relationship.   
     
     
       16. In apparatus as set forth in claim 15, wherein: said openings in said reinforcing assembly are presented by aligned apertures drilled through each of said backing plates.   
     
     
       17. In apparatus as set forth in claim 16, wherein: said openings have a greater axial length than said holes.   
     
     
       18. In apparatus as set forth in claim 16, wherein: said axes of said openings are arranged in a rectangular, matrix pattern.   
     
     
       19. In apparatus as set forth in claim 1, wherein: the spacing between said axes of adjacent ones of said openings is approximately twice the spacing between said axes of adjacent ones of said holes.   
     
     
       20. In apparatus as set forth in claim 19, wherein: said openings are substantially cylindrical and have a diameter of at least approximately twice the diameter of said holes.   
     
     
       21. In apparatus as set forth in claim 20, wherein: said openings have a diameter of approximately 0.078 inch.   
     
     
       22. In apparatus as set forth in claim 20, wherein: the extremity of each of said openings adjacent said face is in communication with the extremity of four of said holes adjacent said other surface.   
     
     
       23. In apparatus as set forth in claim 1, wherein: the extremity of each of said openings adjacent said face partially overlaps with the extremity of each of the holes with which it is in communication.   
     
     
       24. In apparatus as set forth in claim 1, wherein: said securing means includes means bonding a marginal portion of said face of said reinforcing assembly to a marginal portion of said other surface of said holding assembly.   
     
     
       25. In apparatus as set forth in claim 24, wherein: said support plates and said backing plates are formed of fiberglass material, and   marginal portions of adjacent ones of said support plates and said backing plates are bonded together with an electrically insulative epoxy bonding material.   
     
     
       26. In apparatus as set forth in claim 1, wherein: said holding assembly includes a plurality of electrically insulative, support plates in stacked relationship,   said reinforcing assembly includes a plurality of electrically insulative, backing plates in stacked relationship,   said backing plates being of greater thickness than said support plates.